1. Field of the Invention
The present invention relates generally to the field of water treatment using chlorination means, and more specifically relates to a chlorine tablet chlorinator vacuum evacuation system.
2. Description of the Related Art
The most utilized and cost effective method of treating drinking water in modern water systems is with chlorine. Chlorine gas is a strong oxidizer and effectively kills microscopic pathogens rendering the water safe to drink from organic constituents such as viruses, bacteria, and other microbial organisms. Other methods of water disinfection may be utilized as well, such as ozone, ultraviolet light, hydrogen peroxide, filtration, chloramines, chlorine dioxide, and combinations or variations of these as well as other methods. Whichever method of disinfection is used, it must be reliable in view of public health concerns.
In 1974, congress passed the Safe Drinking Water Act in response to a lack of uniform standards between federal, state, and local agencies which varied the safety of the drinking water from locale to locale. The act established a cooperative program between all agencies setting maximum acceptable levels for certain contaminants commonly found in drinking water, and set requirements for treatment methods, system testing, and water system record keeping.
Due to its reliability and cost effectiveness, chlorine gas has been the most widely used method for water treatment. Chlorine oxidizes organic substances on contact and provides a reasonable assurance that the water is safe to drink when a free chlorine residual is detected. A free chlorine residual of at least 0.2 parts per million is required by all agencies. Chlorine gas is also the most dangerous element to use in the water treatment process. Operators that work with gas chlorination systems must be highly trained and certified due to its lethal nature. Many states require that any type of chlorine treatment system that has a potential to discharge dangerous gases into space designed for human occupation to install air scrubbers. Air scrubbing equipment is typically costly to install. Accidents and fatalities in water systems using chlorine gas prompted the EPA and state agencies to tighten regulations on its methods of use. Many water systems turned to tablet chlorination systems. Chlorine tablets are a combination of inert ingredients and chlorine gas. The chlorine gas is bound with the inert ingredients, but the gas continuously liberates from the inert ingredients at various rates depending on the specific composition of a tablet and/or manufacturer.
Chlorine gas leaks in water systems pose a serious threat to health and life for an exposed operator. The level considered to be Immediately Dangerous to Life and Health (IDLH) is the low level of 25 parts per million. The occurrences of exposures have been reduced greatly by the increase in usage of tablet chlorinators but because of the off-gassing of chlorine tablets, a danger still exists, although reduced. A building housing any chlorinator must meet certain design requirements in regards to ventilation and rates of air change, however, ventilation usually will only begin to occur with the opening of a man door. Rarely does an operator wait for ventilation to occur before entering a room that houses a chlorinator. Additionally, tablet chlorinators tend to burp a considerable amount of liberated chlorine gas past the lid seal of a tablet chamber during a back pressure event. Back pressure most commonly occurs when water flow reverses direction momentarily as a water-well shuts down, forcing chlorine gas contained within the sealed tablet chamber past the lid into the room with anyone present. Depending on the proximity to a tablet chlorinator during this event, an operator can easily be exposed to toxic levels of dangerous gas. An effective and cost-effective solution to this safety issue is needed.
Various attempts have been made to solve the above-mentioned problems such as those found in U.S. Pat. Nos. 5,810,043; 6,544,414; 4,260,587; and 4,780,197. This prior art is representative of tablet chlorinators. None of the above inventions and patents, taken either singly or in combination, is seen to describe the invention as claimed.
Ideally, a chlorine tablet chlorinator vacuum evacuation system should provide continuous and complete chlorine gas removal and longevity in-use, and yet, would operate reliably and be manufactured at a modest expense. Thus, a need exists for a reliable chlorine tablet chlorinator vacuum evacuation system to safely remove liberated chlorine gas from the tablet chlorinator, and to avoid the above-mentioned problems.